The invention relates to a method of and to an apparatus for applying labels. More particularly, the invention relates to improvements in methods of and in apparatus which can be utilized to apply labels (e.g., large labels) to bulky and heavy objects. Typical examples of bulky and heavy objects are rolls of convoluted paper which are normally draped into envelopes consisting of paper or other material and are ready to be provided with labels prior to leaving the paper making, rolling and draping plant or prior to being transported to storage.
Published German patent application No. 37 40 093 of Turkki discloses a label applying apparatus wherein an arm which is pivotable about a fixed horizontal axis carries a suction plate and a roll. The suction plate attracts a label when it is pivoted to a position remote from a cylindrical body of convoluted paper so that the label overlies the suction plate and the roll and can be severed from a series of coherent labels. The arm is then pivoted toward the cylindrical body so that a portion of the label adheres to the cylindrical body before the latter is set in motion relative to the arm and relative to the suction plate and the roll on the arm.
A drawback of the apparatus of Turkki is that the cylindrical body must be moved relative to the arm in order to entrain the label and to enable the roll to press successive increments of the label against the cylindrical body. As a rule, the cylindrical body is held for rotation about a horizontal axis. A cylindrical body which consists of convoluted paper is very heavy and extremely bulky so that the energy requirements of the conveyor means for such cylindrical body are very pronounced. Moreover, and since the body is very heavy and bulky, it is difficult to bring it to a halt in an optimum position for the application of a label at a selected location. This often necessitates repeated back and forth movements of the conveyor for the cylindrical body. Still further, proper positioning of the label on the suction plate with reference to the roll also presents problems; it happens again and again that only a portion of the label is actually rolled onto the cylindrical body.
The cylindrical body is normally maintained in such orientation that its axis is horizontal. This means that the label is applied in the circumferential direction of the rotating body. If the label is to be applied to the one or the other end face of the cylindrical body, the latter must be moved linearly along a horizontal path past the suction plate and past the roll at the free end of an arm which is then mounted for pivotal movement about a vertical axis. In other words, it is necessary to provide a first apparatus for the application of labels to the peripheral surfaces of cylindrical bodies, and a second apparatus for the application of labels to the end faces of such cylindrical bodies.
U.S Pat. No. 4,725,327 to Matuda et al. discloses a so-called labeling robot which serves to apply labels to block-shaped objects while the objects are mounted on and are transported by a conveyor. The apparatus which is disclosed in this patent exhibits the same drawbacks as the apparatus of Turkki.
German Pat. No. 677,885 to Albersmann discloses a machine which is designed for the application of elongated strip-shaped labels over the closures of bottles. The patented apparatus employs a label feeder which presses one end of an elongated label against the side of the neck of a bottle which is to be provided with a label, and a roll which is mounted on a rather complex linkage and is caused to drape the label around the closure of the bottle. The manner in which the label feeder receives and/or transports the labels is not disclosed; in fact, the patent does not disclose whether the label feeder is movable or stationary. The bottle which is to be provided with a label must be maintained in horizontal position.
Austrian Pat. No. 352,637 to Green Shield Trading Stamp Company Ltd. discloses a label applying machine wherein the object to be provided with a label must be moved on a conveyor past an indexible label-applying turret and thereupon past a roll which is made of foam rubber and is supposed to press the label against the object. The apparatus of this patent is rather complex and exhibits the same drawbacks as the apparatus of Turkki and Matuda et al.